Cancels this Job and waits for any asynchronous, server-side operations to be canceled. The job is canceled and will result in a JobStatus.Failed status after all cancellation tasks have completed. For jobs running on a server, a cancel request is sent for the associated Job.serverJobId. You should always cancel unneeded jobs (for example when exiting your app) to avoid placing unnecessary load on the server. Examples of server-side jobs include:
Initiates a request to check the server status. If the job is polling the server for status and is in a time gap, then calling this method will ensure a request is sent right away. The result can be false if the job is not checking server status for example if the job status is paused or uploading.